The Buttons below will take you through
the different hints and tips that I feel will make your helicopter
safer and more reliable.
Control Movements and Stops
Ease of control movement
Controls should be smooth and not tight in all
directions of intended travel.
If any control seems tight then find the area of excessive friction
and relieve the friction. This may require lubrication or loosening
up the mechanical clearances to allow for smooth movement.
All control stops need to have thread locker or some other positive
safety method applied so that they cannot move during flight thus
blocking your controls. This happened to me in California with a
student where I had no left cyclic control at 50feet agl and thought
I would loose the ship, it would only go forward and right with
very little control as the helicopter accelerated and leaned to
the right. I took the controls from my student and was amazed that
the helicopter survived the resultant controlled near-crash with
no damage. My guardian angel was watching out for me once again.
This experience once again shows the strength of the Rotorway helicopter
design with its sturdy frame that protects the occupants.
The cause of the restriction was the passenger side left cyclic
stop bolt. The aluminum hole was slightly oversized. The builder
had tightened the lock nut but when the controls were run against
the stops prior to engine start there was just enough play in the
aluminum threads to allow the bolt to rock. When the bolt head moved
upon contact with the tube stop, it shifted just enough to allow
the jam nut to break it's jamming function and the bolt was able
to back out with gravity and vibration as we flew. If the jamming
function of the jam nut is lost, and the bolt can rotate, it can
then back out and prevent control movement in that direction. I
now advocate placing some removable (not permanent) thread locker
on these threads to give a back-up for safety. Check your cyclic
stop bolts and insure that they are properly secured and will not
back out on their own.
The below photo shows where we hit first (diagonal
skid marks to the right), tipped forward onto the nose of the skids
(see Rocking Horse skids) under the landing gear hints and tips)
then the helicopter pivoted around the front left skid about 45
degrees to the left with the front of the left skid digging out
a large divot of sod (the dark clump in the photo). The deep skid
impression was made as we settled back level onto the skids, can
be clearly seen in the photo.
In this case the ground was very soft, as you
can see in the photo. Instead of the left skid kinking at the front
of the left landing gear weldment, which usually happens, the nose
of the skid dug into the soft sod like a cookie cutter and as the
ship pivoted around (tail moving to the left) the buried front left
skid area, it cut out the piece of sod that you can see overturned
in the photo.
This instance was as close to a roll over as one
can get without actually going over. We found the reason for the
control lockup and fixed it right there where the helicopter landed.
We then did a very thorough pre-flight inspection looking for any
damage and found none. After about an hour on the ground, we fired
the helicopter back up, lifted off and resumed our flight training
and continued without problems for the rest of the week when my
student was soloed. After our flight I walked back out into the
field with my camera to take the below photo so that others can
see- proof positive- how the Rotorway helicopter reacts to a full
touchdown emergency landing with forward ground speed. The impressions
in the soft soil tell the entire story.
photo above dramatically shows how the weight of the helicopter
is transferred to the front left skid.
Even after all of the
publishing of the control lockup issue that I experienced,
some owners are still not checking their controls. On
March 15, 2008 I was hired to provide insurance qualification
training for the new owner of a 200 hour Rotorway 162F.
This ship was being regularly flown and had been flown
by a "Rotorway Flight Instructor" at a new flight
school with very little experience. The insurance company
required that the instructor that was to give the qualification
training have at least 1000 hours in Rotorway Helicopters,
for very good reason.
When I arrived at the
airport I first gave the helicopter that I would be flying
a very good safety inspection. There were several issues
that I dealt with and adjusted. I told my student to remove
the cyclic control cover panels so that I could inspect
all of the controls. This ship had a fresh annual inspection
so it had been "inspected" by someone "Qualified".
The photo above shows what I found on this ship that was
regularly flying and just recently with a "Rotorway
Experienced" flight instructor!
The cyclic control stops
had no jam nuts on the stop bolts, there was no lock tight,
and I easily unscrewed them with my bare fingers, all
four of them. These bolts are hanging upside down where
gravity will cause them to unscrew. The fact that a flight
instructor who is represented as being Rotorway qualified
to students had flown this ship without even checking
the controls is frightening. He appears to be a really
nice guy and he is instructing Rotorway builders in their
own machines, he just does not have the experience that
only years of instructing and maintaining these machines
Just because someone
signs off an annual inspection does not mean that they
actually performed the inspection.
Just because someone
says that the are a Rotorway Experienced flight instructor,
that may mean that they have the required 5 hours in type.
is another photo of the other cyclic control, it too had
the unsecurred cyclic stop bolt just hanging there. These
bolts were not installed according to the kit manufacturers
instructions and drawings.
One other area where I experienced a control lockup in flight
was with the donut-shaped collar around the main rotor shaft under
the non-rotating swash plate on the Rotorway helicopter. This
collar must be secured to the main shaft by clamping pressure
so that it cannot slide up or down. In this case I was with a
student when the collective controls locked in the near full-up
position. This happened in an area where the wind was high and
gusting higher as my student was making an approach to the fuel
tanks on his ranch. Controlling the helicopter, a Jet Exec non-factory
configuration, in the gusty winds was requiring a lot of collective
input when all at once the collective locked in the near-full
up position. It is important to note that the jet engine equipped
ships vary greatly from the design of the Rotorway helicopter
and their reliability history should not be compared with that
of a Rotorway built to factory specs.
The helicopter began to climb, and climb fast, with the powerful
turbine engine powering it's rotor system. I emphatically called
out to my student "I've got
it", those special words that I reserve for
the times when I need the student completely off of the helicopter's
controls. I took the controls and decreased the throttle on the
Jet Exec to achieve a main rotor RPM of around 92 percent, thus
producing less thrust and the helicopter settled to the ground
where I was able to slide it on (it had the extended skid modification).
A word of caution here, we were in a life and death situation
and the only way that I could stop the rapid climb was to reduce
the main rotor RPM to decrease the lift being produced. Doing
this in flight and especially in a high rotor pitch angle climb
is very risky and if the rotor RPM is allowed to decrease much
below that point the main rotors will stall and the helicopter
will fall like a rock. I had no choice and did what I needed to
do to cause the helicopter to descend and slide onto the surface.
Upon investigating the cause of the lock-up we discovered the
problem. My student had purchased a rolled over helicopter in
Texas. The torque on the nut securing the collar to the main rotor
shaft had been checked by me when I arrived a the students home.
The torque value on the NUT was correct but the collar still slipped
down allowing the alignment forks to exit the top of the collar
and rotate away from their slots in the collar. The forks now
effectively blocked the collective control from moving the swashplate
downward to lower the pitch on the main rotor blades.
Upon examination after the lockup we found that the clamping
bolt had corroded threads. The bolt thread condition caused the
nylock nut to achieve the proper torque, but before the nut was
far enough onto the bolt to securely clamp the collar to the shaft.
The person installing the collar must have used a defective bolt
to secure it. I now gently but firmly pry down on the collar on
every ship I apply downward pressure on the collar to insure that
it has the proper clamping pressure so that it will not move.
I also check the torque on both the nut and the bolt head to insure
that both are at the proper setting to achieve the required clamping
force on the collar.
The photo below was taken after we landed. You can clearly see
the forks sitting out of their slots and resting on top of the
collar which prevents them from being able to be lowered.
After we repositioned and securred the collar above and completed
Ron's flight instruction, I headed to Pennsylvania to provide
another student with advanced flight training. I was performing
an airworthiness inspection on this student's Rotorway Exec 90
when I noticed the collar position looked too low. When I pulled
full up-collective the fork came completely out of the collar.
We checked the torque settings and they were incorrect for the
nut and bolt head, they were loose.
This student had been flying it that way at altitude and if he
had ever been put into the position of applying full up-collective
the fork would have come out of the guide slots and rotated away
from them. This would again have jammed the collective in the
full-pitch position. Had that happened it could have ended up
in an unhappy ending! Everyone should check the position and security
of this collar. That was the second collar issue found in 2 weeks.
The photo below was taken before we slid this second collar back
into position and properly torquing the clamping bolt.
method of securing the collar to the main shaft is very
effective but the installation must be done to the factory
standards. It is the responsibility of the owner/builder
to check the integrity of the clampinb bolt to insure proper
securring of the collar to prevent it from moving.
above shows a properly placed collar and this builder also
fabricated a reinforced collective scissor bracket. I have
seen this bracket break in the past. The break occured at
the 90 degree bend and is most likely from improper technique
used in bending the bracket ears performed by the builder.
Those bends should be radiused as per the factory drawings.
The following week I was off to Connecticut and of course now
the first thing on this students ship that I checked was his locking
collar. When I applied downward pressure on the collar with a
piece of wood and a fulcrum the collar slipped down easily. We
checked the torque on the nut and it turned and turned and turned
but would not tighten. It took us nearly an hour to get the locknut
with stripped threads off the bolt and as you can clearly see
in the photo below the installer had used a bolt that was the
next size longer than called for in the factory specs.
When the nut was tightened it ran out of threads and rode up
onto the shank of the bolt stripping the nut's threads. With the
threads stripped the collar could not apply the required clamping
force onto the main rotor shaft. It could have eventually slid
down to the point that the forks could clear the collar, rotate,
and jam the collective in the full up-collective position.
I urge everyone to check their collars prior to flight. This
series of loose collars is not common because I have only found
one loose clamping ring since.
There is one area on the Rotorway where sometimes there is not
enough clearance for the pilots left hand during the initiation
of an auto-rotational descent. This is the area of the left collective
pocket against the outer wall of the cabin. If the throttle is
too close to allow the back of the pilot's hand and knuckles to
be able to fully lower the collective into the pocket to achieve
full negative pitch on the main rotor blades, some adjustment
or modification to this area may be desireable. During auto training
the student might be forced to slide his/her hand to the front
end of the throttle and hold it with the tips of the fingers if
there is not enough room in this area.
I have found that a Dremmel tool with an abrasive disc cutter
is the tool of choice for this simple modification. I make a cut
from the front of the pocket to the rear on the flat bottom just
inboard of the curved section where the fiberglass makes the transition
from the horizontal floor to the vertical wall of the pocket.
I then cut both sides up to the top of the pocket and then out
to within about 1/4" inboard from the outer body skin panel.
I then finish the removal by cutting along the outer body panel
and about 1/4" in from the edge.
I leave the 1/4" piece so that there is something to attach
new fiberglass to when the new pocket is later formed. This is
usually accomplished by utilizing the piece of fiberglass that
was removed but can now be moved outward as far as possible to
allow clearance for the pilots hand and knuckles when the collective
is fully lowered. It can then be glassed in, smoothed and painted
for a factory finish. Since we usually do not take the time to
re-glass the pocket during training, we place some duct tape over
the cut fiberglass edges to protect the pilots knuckles.
Check the fit on your collective and determine if you can fully
lower it into the pocket with your hand around the throttle. I
want to thank Todd Mason for sending the below photo of his side
pocket with the section removed. This gives him the needed hand
clearance for autos and he can take care of the esthetics later,
see photos of a comparison of the stock and modified pockets
Richter provided us with a great tutorial on how he modified
the collective pocket on his Rotorway 162F
Pocket Mod Page 1 (Click Picture)
Pocket Mod Page 2 (Click Picture)
The material on each page is the opinion of the author only and
any actions taken by the reader relating to information on this
site is the responsibility of the builder.